Process for separating cobalt from ores or by-products.



iunirnn s raa ns PATENT enrich PHILIP M. MCKENNA, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR. TO CHEMICAL PRODUCTS COMPANY, OF WASHINGTON, DISTRICT OF COLUMBIA, .A. CORPORATION OF WEST VIRGINIA.

PROCESS FOR SEPARATING COBALT FROM ORES OR BY-PRODUCTS.

No Drawing.

To all whom it may concern.

Be it known that I, PHILIP M. MoKnNNA, a citizen of the United States, residing at lVashington, in the District of Columbia, have invented certain new and useful Improvements in Processes of Separating Co balt from Ores or By-Products; and I do hereby declare the following to be a full, clear, and exact description of the same.

The present invention has for its object the, economical separation of cobalt metal in a substantially pure condition' from ores or by-products containing the same, the invention being particularly adapted for the treatment of ores or by-products containing a large percentage of arsenic in proportion to the cobalt. Ores or by-products containing a small percentage of arsenic may be mixed with ores or by-products containing an excess, or arsenicmay be added to increase the arsenic content to best adapt the same for treatment by the present process and hence it is not desired to limit the invention to the treatment of any particular raw material containing cobalt.

The raw material, ore or by-product containing cobalt is firsttreated to produce a speiss containing the cobalt and nickel, etc. This step of the process is conveniently performed in a furnace at a temperature of approximately 1200 C., preferably regulated to have a slightly reducing atmosphere, under which conditions a speiss is formed which when the fused mass is poured into a mold, collects at the bottom because of its greater specific gravity. A typical speiss may contain: 22.4% G0, 13.9% Ni, 10.6% Fe, 45.0% As, 3.6% Sb. The speiss is next treated to reduce the percentage of arsenic nd this is preferably accomplished by comminu-ting the same as by grinding and then roasting in afurnace, the atmosphere of which is preferably alternately oxidizing and reducing. Favorable results are secured by grinding the speiss to pass a 60 mesh screen and during the initial roasting it should be heated to only a low red heat to prevent agglomeration, although the heat may be subsequently raised to a bright red; The action is accelerated by stirring during the roasting operation. The reduction in the percentage of arsenic may be within rather wide limits, thus, the percentageremaining may be from 8 to 23%. In this condition Specification of Letters Patent.

Patented Dec. 28,1915.

the speiss is ready for the succeeding operation which is based on.the discovery that when the speiss'is fused with boron trioxid the cobalt combines with the boron in a much greater percentage than doeswthe nickel,- with the result that a gravity separation oi 'the nickel arse'nid speiss and boric cobalt slag may be effected. The fusion is preferably effected in a furnace of the Schwarz type run with a neutral flame, although any furnace capable of a heat of 1200 C. and whose hearth is lined with silica willanswer.

The melt is made at a temperature which will keep the fusion liquid, usually 1000 (l, and the quantity of B 0 added is preferably by weight approximately equal to the weight of cobalt contained inthe speiss. 1f commercial boric acid be used the quantity employed should be figured on the B 0, content. As an example, if a speiss containing 24% cobalt and 16% nickel be fused with a weight of B 0, equal to the Weight of the cobalt in the speiss, approximately 87% of the cobalt will be extracted into or combined with the boric acid with enough nickel to make the proportions 6.2 cobalt to l nickel, and the nickel-arsenid will contain nickel and cobalt in ratio of 4.2 to 1. The iron in the speiss will be with the cobalt portion. The nickel arsenid speiss is separated from the boric cobalt slag by pouring the melt into a mold and while still hot, decanting the slag back into the hot furnace leaving a nickel arsenid button in the mold. The atmosphere in the furnace is now made of a more reducing character. nace this is accomplished by increasing the oil supply and cutting off the air supply.

After about one-half hour, the melt is poured used in making the speiss, but which is kept free from arsenic or antimony ores. Here it is heated as hot as possible with an oxidizing flame to expel any remaining arsenic or antimony. After about three hours it is In a Schwarz fur-.

other furnace which may be similar to that speiss containing the poured and may be allowed to cool before the next operation which consists in charging the mass into an electric furnace where the cobalt, -With some iron is reduced out as metal by heating with carbon and forms the finished product.

If iron be undesirable the speiss -used should be freed from iron by melting with silica before roasting.

The boric acid may be used over again until it becomes too much diluted with silica, etc, from the furnace lining.

Obviously the process may start with a speiss of the character described regardless of the manner of producing the same and the separation of the cobalt from the bone cobalt slag may be effected otherwise than as herein speci cally set forth, although the process described is preferred because of its efliciency and economy.

Having thus described my invention, What I claim as new and desire to secure by Letters Patent is, i

1. The process of separating cobalt from a speiss containing the same, which consists in efiecting fractionation by fusing the speiss with boron-triox'id.

2. The process of separating cobalt froma speiss containing cobalt and nickel, which consists in fusing the. speiss and boron-trioxid and causing the nickel arsenid spciss to separate from the boric cobalt slag by reason of the difference in their specific gravity.

3. The process of separating cobalt from a same, which consists in fusing the speiss' and boron-trioxid, sepaslag.

The process of separating cobalt from a speiss containing the same, whlch conslsts in fusing the speiss and boron-trioxid, separating the arsenid speiss and boric cobalt slag and in heating the latter to approxiniately-1000 C. under oxidizing conditions to expel arsenic and antimony from the cobalt oxid in the slag.

(3. The process of separating cobalt from a speiss containing the same, which consists in producing therefrom a boric cobalt slag in which the cobalt exists as a cobalt oXid and in reducing the cobalt oxid'to a metallic condition.

7. The process of separating cobalt from a speiss containing the same, which consists in producing therefrom a bone cobalt slag in which the cobalt exists as an oxid and in reducing the cobalt oxid to a metallic conditionvin an electric furnace in. the presence of a reducing agent.

PHILIP M. MCKENNA.

Witnesses:

A. G. MoKnnNA, J. R. GAIN. 

